diff options
author | Oliver Neukum <oneukum@suse.com> | 2016-03-15 10:14:04 +0100 |
---|---|---|
committer | Sasha Levin <sasha.levin@oracle.com> | 2016-04-18 08:51:03 -0400 |
commit | a635bc779e7b7748c9b0b773eaf08a7f2184ec50 (patch) | |
tree | 0545bc8de899c6bb4c57d6729de1e82a2217ca0f | |
parent | febfaffe4aa9b0600028f46f50156e3354e34208 (diff) |
USB: cdc-acm: more sanity checking
[ Upstream commit 8835ba4a39cf53f705417b3b3a94eb067673f2c9 ]
An attack has become available which pretends to be a quirky
device circumventing normal sanity checks and crashes the kernel
by an insufficient number of interfaces. This patch adds a check
to the code path for quirky devices.
Signed-off-by: Oliver Neukum <ONeukum@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
-rw-r--r-- | drivers/usb/class/cdc-acm.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index df3deb000a80..09084c9da8b7 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -1118,6 +1118,9 @@ static int acm_probe(struct usb_interface *intf, if (quirks == NO_UNION_NORMAL) { data_interface = usb_ifnum_to_if(usb_dev, 1); control_interface = usb_ifnum_to_if(usb_dev, 0); + /* we would crash */ + if (!data_interface || !control_interface) + return -ENODEV; goto skip_normal_probe; } |